Pre-process functions in Drupal allow you to modify variables before they are passed to templates. This document discusses using the template.php file to define pre-process functions for nodes, fields, and other areas. It recommends tools like Devel and Firebug that can help debug pre-processing and see available variables. Pre-processing can be used in many places like nodes, pages, views and more.

1. Pre-Process Functions in
Template.php
June 22, 2012

2. Harris Rashid
Themer & Developer
@harriszrashid
harris@chapterthree.com

3. Theme Structure

4. What is it & when does it happen?
Pre-Process

5. Processingweb request

6. Processingweb request
Raw Data (from DB)
Return Data (modules)

7. Processingweb request
Raw Data (from DB)
Return Data (modules)
Formatted Data (themes)
HTML

8. $content in node.tpl.php & page.tpl.php

9. Tools
- Devel module
- Admin menu module
- Firebug firefox plugin

10. Floated Right

11. Floated Left

12. Tools
yourtheme_preprocess_node
($variables)

13. Variables
Drupal 7: $variables
Drupal 6: $vars

14. How do I use preprocess with Fields?
- Image (file)
- Image Caption (image description)
- Image Alignment (text - radio buttons)

15. Create a template.php file, turn on the Devel Module,
and use the DSM function.

16. Refresh your node page twice, and you
should see the Kufon display of the node.

17. We're going to need the following values for
field_image, field_image_position

18. More Resources
http://drupal.org/node/223430
http://api.drupal.org
Pre-Process can be used on
Nodes, Pages, Search Results,
Views, User Pictures, and a host
of other places in Drupal.